The nRF52820 is supported by the S112 and S140 SoftDevices (Bluetooth 5.1-qualified protocol stacks), and the S122 (alpha version) SoftDevice. The S112 and S122 are memory-optimized peripheral and central stacks respectively, while the S140 is a feature-complete Bluetooth 5 protocol stack for central and peripheral, including Long Range and high-throughput 2 Mbps features.
Development with the nRF52820 is supported by Nordic's nRF5 SDK v16.0.0, with full nRF5 SDK support to follow in Q2 2020. The nRF52833 Development Kit (DK) can be used to emulate the nRF52820. The DK is a versatile single board development kit for Bluetooth LE, Bluetooth mesh, 802.15.4, Thread, Zigbee, and 2.4GHz proprietary applications. The DK is compatible with the Arduino Uno Rev3 standard.